Obstructive Sleep Apnea (OSA) and other dangerous sleep-disordered breathing (SDB) conditions affect millions worldwide. Numerous techniques have emerged for the treating SDB, including, for example, the use of Continuous Positive Airway Pressure (CPAP) devices, which continuously provide pressurized air or other breathable gas to the entrance of a patient's airways via a patient interface (e.g., a mask) at a pressure elevated above atmospheric pressure, typically in the range 3-20 cmH2O, or higher. SDB might also be treated with a high flow treatment device via a nasal cannula or other nasal patient interface such that the high flow treatment device generates warm humidified breathable gas or air at flows that may range from about 1 to 60 liters per minute. Typically, patients suspected of suffering from SDB register with a certified sleep laboratory where sleep technicians fit patients with numerous data collectors (e.g., polysomnography) and monitor their sleep activity over a given period. After the patient is diagnosed, a treatment regimen usually is developed, identifying both a treatment apparatus (or treatment apparatuses) and program of use for the treatment apparatus(es).
FIG. 1 is a partial schematic view of a typical positive airway pressure (PAP) device. An impeller 1 is powered by an electric motor 2 using a servo 3 under the direction of a microprocessor-based controller 4 (sometimes called a processor). The supply of breathable gas is carried to the mask 5 through a flexible conduit 6. The apparatus has various switches 7, displays 8, and a number of transducers. The transducers may monitor a number of processes, such as, for example volumetric flow rate 10 (e.g., at a predetermined point in the flow path), pressure 11 (e.g., at a predetermined point downstream of the flow generator outlet or at the mask), snore 12, flow generator rotational speed 13, and/or motor parameters 14.
Some treatment devices currently implement a series of algorithms that assess different respiratory parameters (such as, for example, snore, flattening, apnea, etc.) and then adjust the delivered pressure according to predetermined conditions. Only the total delivered pressure is reported to the clinician and/or patient. Certain other current products have been used to report a number for each pressure aspect. U.S. Pat. Nos. 5,245,995, 6,398739, 6,635,021, 6,770,037, 7,004,908, 7,141,021 each relate to automatically adjusting PAP devices, and the entire contents of each hereby are incorporated herein by reference.
It is advantageous to track the treatment pressure over time, for example, to aid in diagnosis and treatment. Unfortunately, however, such techniques either do not present the full range of data or present some or all of the data in a fashion that results in a diminished utility. For example, although some conventional devices present statistical reports, the reports may be difficult to understand and difficult to visualize when trying to obtain a more complete picture of a particular treatment under review and the events that led to the specific treatment being taken by an automatically adjusting PAP device. At least some of the information typically is in the PAP device, but it is difficult or impossible to access, or is simply not organized or presentable to the patient and/or clinician in a way that is helpful for diagnosis and/or treatment.
Thus, it will be appreciated that there is a need in the art for improved techniques for understanding how the delivered pressure is calculated.